Object expected Error when I use a4j:ajax happens only IE8

For a job, I have to use only IE8 as a browser. When I use a4j:ajax event it gives me "Object expected" error and in IE8 Developer tools it tells that this "Object Expected" comes from rich:messages that I used before.

This issue only happens in IE8 and it happens when I use a4j:ajax event. Even when I use only <a4j:ajax event="dblclick"> without any other tag, I still come across with "Object Expected" javascript error which comes from rich:messages .. You can see code of the exact poing where error happens and my <rich:message> declaration below.